DDEC is designed to operate with several types of sensors as listed in Table “Sensor Types” .
| Sensor Type | Description |
| Variable Reluctance/Magnetic Pick-up | Used to monitor the crankshaft position, engine speed, turbo speed, and vehicle speed. |
| Thermistor | Used to monitor temperatures. |
| Variable Capacitance | Used to monitor manifold, and oil gallery pressures. |
| Variable Resistance (Potentiometer) | Used to sense throttle position. |
| Switch | Used to signal coolant level. |
Table 1. Sensor Types
The sensors integrated into the Engine Harness are factory-installed (refer to “17.7.1 Factory-installed Sensors” ). The sensors integrated into the Vehicle Interface Harness are installed by the OEM (refer to “17.7.2 OEM-installed Sensors” ).
Factory-installed Sensors
The sensors integrated into the factory-installed Engine Harness are listed in Table “Function of Factory-installed Sensors” .
| Sensor | Function |
| Camshaft Position Sensor (CMP Sensor) | Indicates a specific cylinder in the firing order. |
| Crankshaft Position Sensor
(CKP Sensor) |
Senses crankshaft position and engine speed for functions such as fuel control strategy. |
| DPF Inlet Pressure Sensor | Sensor measures pressure between the Diesel Oxidation Catalyst (DOC) and the Diesel Particulate Filter (DPF) in the aftertreatment assembly located in the exhaust system of the vehicle. |
| DPF Outlet Pressure Sensor | Sensor measures pressure on the outlet of the after-treatment device in the exhaust system of the vehicle. Located after the DPF that is within the aftertreatment device. |
| DPF Outlet Temperature Sensor | Temperature measured at the outlet of the after-treatment system that is installed within the exhaust system of the vehicle. It’s located after the DPF that is within the aftertreatment unit. |
| DOC Inlet Temperature | DOC Temperature In – Temperature measured at the inlet of the after-treatment device in the exhaust system of the vehicle. Located before the DOC that is within the after-treatment device. |
| DOC Outlet Temperature | Temperature measured between the DOC and the DPF in the aftertreatment assembly located in the exhaust system of the vehicle. |
| EGR Delta Pressure Sensor
EGR Delta P Sensor |
Senses EGR pressure for EGR control. |
| EGR Temperature Sensor | Senses EGR exhaust temperature after EGR cooler. Used for EGR system diagnosis. |
| Engine Coolant Temperature Sensor (ECT Sensor) | Senses coolant temperature for functions such as engine protection, fan control and engine fueling. |
| Engine Oil Pressure Sensor
(EOP Sensor) |
Senses gallery oil pressure for functions such as engine protection. |
| Engine Oil Temperature Sensor (EOT Sensor) | Senses oil temperature for functions such as reducing variation in fuel injection and fan control. |
| Fuel Line Pressure Sensor | Senses fuel line pressure |
| Fuel Compensation Pressure Sensor | Compensates fuel line pressure |
| Intake Manifold Pressure Sensor (IMP Sensor) | Senses turbo boost for functions such as smoke control and engine protection. |
| Intake Manifold Temperature Sensor (IMT Sensor) | Senses boost temperature |
| Supply Fuel Temperature Sensor (SFT Sensor) | Senses fuel temperature for functions such as engine fueling. |
| Turbo Compressor Temperature Out Sensor | Senses turbo out air temperature. |
| Turbo Speed Sensor (TSS) | Monitors turbo speed. |
| Water-in-Fuel Sensor
MBE 900 and DD15 Engine Only |
Detects water in the fuel filter that alerts the owner/driver that the fuel filter needs to be dried out. |
Table 2. Function of Factory-installed Sensors
See Figure “Sensor Location for the DOC and DPF” for the location of the sensors for the DOC and DPF.
| 1. Dosing Fuel Line | 7. DOC Inlet Temperature Sensor |
| 2. Doser Block Assembly | 8. DOC Outlet Temperature Sensor |
| 3. Fuel Pressure Regulator | 9. Sensor Junction box |
| 4. Intake Throttle Valve | 10. DPF Outlet Temperature Sensor |
| 5. EGR Valve | 11. DPF Outlet Pressure Sensor |
| 6. Fuel Doser Valve | 12. DPF Inlet Pressure Sensor |
Figure 1. Sensor Location for the DOC and DPF
